The human spine consists of a complex set of interrelated anatomic elements including a set of bones called vertebral bodies. Intervertebral discs separate most vertebral bodies. These discs includes a “spongy” nucleus pulpous surrounded by an annulus fibrosis “membrane”. The annulus fibrosis connects the opposed endplates of adjacent vertebral bodies. All of these structures together with muscles act to provide motion, stability and protection for the spine. When healthy, these structures effectively protect the spinal cord and allow for normal motion.
However there are many disease states and aging processes that impact the patient. Osteoporosis and metastatic disease reduce the structural integrity of the vertebral bodies, predisposing them to fracture. Vertebral fractures can lead to loss of vertebral height which can exacerbate existing neurological condition or it can predispose the spine to other symptoms. Back pain often results from these conditions. Vertebroplasty is an effort to stabilize these fractures and to alleviate this source of pain.
Generally, fractures and loss of height if not treated results in a cascade of injury which is undesirable. For this reason various efforts have been directed at stabilizing and restoring the natural vertebral bodies of the back. Efforts have also been directed to replacing the vertebral bodies. condition or it can predispose the spine to other symptoms. Back pain often results from these conditions. Vertebroplasty is an effort to stabilize these fractures and to alleviate this source of pain.
Generally, fractures and loss of height if not treated results in a cascade of injury which is undesirable. For this reason various efforts have been directed at stabilizing and restoring the natural vertebral bodies of the back. Efforts have also been directed to replacing the vertebral bodies.
U.S. Pat. No. 5,108,404 to Scholten et al among others teaches a technique for height restoration that uses a bone cement product introduced into a cavity after a cavity has been made with an inflatable device. One problem with this system is the extravasation of bone cement to sensitive areas. Another problem is the difficulty of obtaining consistent control of height restoration with the Scholten system.